With the development of data storage technologies, various data storage devices are capable of providing users with increasingly high data storage capability, and the data access speed has also been improved greatly. At the same time of improving the data storage capability, users propose increasingly high demands for performances of the storage system such as response time. Various data storage systems based on Redundant Arrays of Independent Disks have already been developed to improve the performance of the storage system.
For example, currently, mapped Redundant Arrays of Independent Disks (mapped RAID) have already been developed. In the mapped RAID, a disk is a logic concept and may include a plurality of extents. The plurality of extents included in one logic disk may be distributed on different physical storage devices in a resource pool. For a plurality of extents in a stripe of the mapped RAID, the plurality of extents should be distributed on different physical storage devices, so that when a physical storage device fails in which one of the plurality of extents is located on the failed physical storage device, a rebuilding operation may be executed to restore data from the physical storage devices in which other extents are located. However, in an existing solution, if the mapped RAID is being rebuilt, any type of disk copying operations in the same RAID is rejected, even though they are not directed to the same mapping stripe. This weakens the processing capability of the mapped RAID and lowers the performance of the storage system.